Gas-burner



' lowing to be a full, clear,

fairen 'sues parer orifice.

ivan LUNDGAARD, or ROCHESTER, New roux GAS-BURNER.

hind in which a blast or current of air acts to induce the gas and produce a mixture.

suitable Jfor complete combustion.

The general objec of thepresent tion is to produce a urner, of simple' con struction, in which air and lgas are thoroughly and uniformly? mixed and in which the necessity for an'extended mixing-chambe'rl and a guard o'r `grating is eliminated'.

' A further object of the -inventionnis toprol .the Venturi elicot.

l burner embodying ..50

duce a burner which will operate eliectively with an air-blast at a substantially lower pressure than that which has heretofore been necessary.

In the burner ot' the present invention air is forced through an annular passage which flares 'or increases in cross-sectional area toward its .discharge-end, andthe gas is discharged into the stream otair at a zone where the air-stream is constricted inthe narrow part of the passage, so that the gas is sucked `into-'the air-stream in a volume proportionedapproximately to -the volume of air. Preferablythe mixing-passage has a form such aste produce what is .known as paratively constricted gas-orifice, -or a series of such orifices, arranged in it is possible to obtain a homogeneous mixture of gas and air within a very short'dis tance-from the point of gas-admission, thus dispensing with the necessity 'of an extended mixing-chamber and of a or grating. A

ln the accompanying drawings Figure 1. isa longitudinal sectional view of a gasthe present invention, and Figs. 2, 3 and modified forms of the invention.

' The illustrated embodiment'of the invenf tion comprises a `cylindrical outer tube 5 which provides the mixing-chamber and constitutes also the airtube, being fed with Specification of Letters Patent.

AApplication lexi July 31, 1918. Serial No. 212,689.

hereby declare the ol-.

invenv 'burner resides in By the use of a comthe grating. or gauze annular form,v

perforated guard.:

4 are similar views oivform a complete cone,

' ward extremity of the IPatent@ May 25, 1920.

air ata suitable pressure.

centrically -withvrthe tube in any convenient manner. rllhe head is `tapered toward each end, so that the annular passage lbetween at. the most' restricted zone of the passage just describedhthrough an annular series of `Vithin the air@ ltube ois a head 6 which is supported conthe head and the air-tube has a longitudinal small perforations 9 in the head 6. These v perforations discharge from aY central gaslchamber l() in the head, and this chamber is'fed with gas through a pipe 1l arranged concentrically within the air pipe 5. As

shown Ain the drawings the gasepipe constitutes the support fort'he head 6, the gasp'ipe and the air-tube being maintained in concentric arrangement` by any convenient means (not shown). l

.The air, in its movement through the passage 7-8, induces a liow of gas, through the perforations 9, which varies with the volume of air which passes, and owing to the distribution otthe Igas througha considerable number of such perforations', the gas is mingled with the air while passing through the short space between the perforations 9 and the discharge-end of the airtube, so that an intimate mixture is prolduced without the necessity of an extended mixing-cha1nber- AAn important feature of the 'present the fact that the elongated mixing-tube or chamberk usually employed in gas-burners is dispensed with, as well as Y usually necessary to prevent back-firing in 'such mixingtubes. In the present burner, therefore, iteis necessary to maintain -a comparatively high velocity in the combustible mixture while it is passing from the gas-orifices 9 to the open end of the air-tube, in order that the flame may not, under normal conditions, vstrike back too .far into the space within the airtube. For thisireason the iorward part ot 'thel head 6 is taperedat only a slight angle, such that, if the head were 'continued to the apex would lie a considerable distance in front 'of the forair-tube. li' so continued, however the head would be subjected to the heating eect of the dame to a degree required in this which would be inadmissible. Accordingly,

`the head is cut off or truncated at a point i within the air-tube Where it moved from contact with the iiame.

v normal position.

, it 1s usually the air tube, or both,- from the heat of the' Owing to the intimate mixture of the air and the, gas the combustion occurs at and partly within the mixing-chamber, so that desirable to protect the head or flame. InV Fig. 2vthe air-tube is shown as providedwith anannular water-jacket 12 provided with inlet and outlet passages 13 and 14 through which a current of water may be passed. Fig. 3 shows-a means for protecting the head 6, this means having the form of a cap 15 of refractory material such as fire-clay, secured to the head b means ofacross-pin 16. In Fig. 4 the head is similarly. protected, and the air-tube 54 is provided with a tip 17 of refractory material. These protective devices areuseful particularly where the burner is to be regulated through wide degrees, so that combustion may sometimes occur to a considerable is nearly rethe air-tube near Lampes .exltent within'the discharge-end of the-airftu e. f-

tinct narrow orifices, this detail is adopted merely for convenience in construction, the

essential feature being the'introduction of the' gas substantiallythroughout the con- -stricted zone of the mixing-passage.

rlhe invention is notI limited to the em` bodiment thereof hereinbefore described and illustrated in the accompanying drawings,but it may be embodied in various other forms within ing claims. The invention claimed is 1. A gas-burner comprising: an air-tube serving, at its forward open end,- as a mixing-chamber 'said .end and provided with annularly arranged gas-outlet openings; and means for supplying gas to said head; the headbeing substantially of greatest diameter at said openings and tapering forwardly therefrom substantially in the form of a cone, of which the apex is locatedl a substantial distance beyond the extremity of the air-tube, but in said eXtremlty.

2. A gas-burner, as in claim 1,l in which the truncated vconical end of the. head has a surface of refractory material.

IVAR LUNDGAARD.

a head, concentric with which is truncated with-- the scope of the followl 

